gdbserver: turn target op 'read_loadmap' into a method

gdbserver/ChangeLog:
2020-02-20  Tankut Baris Aktemur  <tankut.baris.aktemur@intel.com>

	Turn process_stratum_target's read_loadmap op into a method of
	process_target.

	* target.h (struct process_stratum_target): Remove the target op.
	(class process_target): Add the target op.  Also add
	'supports_read_loadmap'.
	* target.cc (process_target::read_loadmap): Define.
	(process_target::supports_read_loadmap): Define.

	Update the derived classes and callers below.

	* server.cc (handle_qxfer_fdpic): Update.
	(handle_query): Update.
	* linux-low.cc (linux_target_ops): Update.
	(linux_process_target::supports_read_loadmap): Define.
	(linux_read_loadmap): Turn into ...
	(linux_process_target::read_loadmap): ... this.
	* linux-low.h (class linux_process_target): Update.
	* lynx-low.cc (lynx_target_ops): Update.
	* nto-low.cc (nto_target_ops): Update.
	* win32-low.cc (win32_target_ops): Update.

gdbserver/ChangeLog

@@ -1,3 +1,27 @@
+2020-02-20  Tankut Baris Aktemur  <tankut.baris.aktemur@intel.com>
+
+	Turn process_stratum_target's read_loadmap op into a method of
+	process_target.
+
+	* target.h (struct process_stratum_target): Remove the target op.
+	(class process_target): Add the target op.  Also add
+	'supports_read_loadmap'.
+	* target.cc (process_target::read_loadmap): Define.
+	(process_target::supports_read_loadmap): Define.
+
+	Update the derived classes and callers below.
+
+	* server.cc (handle_qxfer_fdpic): Update.
+	(handle_query): Update.
+	* linux-low.cc (linux_target_ops): Update.
+	(linux_process_target::supports_read_loadmap): Define.
+	(linux_read_loadmap): Turn into ...
+	(linux_process_target::read_loadmap): ... this.
+	* linux-low.h (class linux_process_target): Update.
+	* lynx-low.cc (lynx_target_ops): Update.
+	* nto-low.cc (nto_target_ops): Update.
+	* win32-low.cc (win32_target_ops): Update.
+
 2020-02-20  Tankut Baris Aktemur  <tankut.baris.aktemur@intel.com>
 
 	Turn process_stratum_target's core_of_thread op into a method of

gdbserver/linux-low.cc

@@ -6483,9 +6483,15 @@ struct target_loadmap
 #  define LINUX_LOADMAP_INTERP	PTRACE_GETFDPIC_INTERP
 # endif
 
-static int
+bool
-linux_read_loadmap (const char *annex, CORE_ADDR offset,
+linux_process_target::supports_read_loadmap ()
-		    unsigned char *myaddr, unsigned int len)
+{
+  return true;
+}
+
+int
+linux_process_target::read_loadmap (const char *annex, CORE_ADDR offset,
+				    unsigned char *myaddr, unsigned int len)
 {
   int pid = lwpid_of (current_thread);
   int addr = -1;
@@ -6515,8 +6521,6 @@ linux_read_loadmap (const char *annex, CORE_ADDR offset,
   memcpy (myaddr, (char *) data + offset, copy_length);
   return copy_length;
 }
-#else
-# define linux_read_loadmap NULL
 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
 
 static void
@@ -7445,7 +7449,6 @@ linux_get_hwcap2 (int wordsize)
 static linux_process_target the_linux_target;
 
 static process_stratum_target linux_target_ops = {
-  linux_read_loadmap,
   linux_process_qsupported,
   linux_supports_tracepoints,
   linux_read_pc,

gdbserver/linux-low.h

@@ -377,6 +377,13 @@ public:
   int handle_monitor_command (char *mon) override;
 
   int core_of_thread (ptid_t ptid) override;
+
+#if defined PT_GETDSBT || defined PTRACE_GETFDPIC
+  bool supports_read_loadmap () override;
+
+  int read_loadmap (const char *annex, CORE_ADDR offset,
+		    unsigned char *myaddr, unsigned int len) override;
+#endif
 };
 
 #define get_thread_lwp(thr) ((struct lwp_info *) (thread_target_data (thr)))

gdbserver/lynx-low.cc

@@ -735,7 +735,6 @@ static lynx_process_target the_lynx_target;
 /* The LynxOS target_ops vector.  */
 
 static process_stratum_target lynx_target_ops = {
-  NULL,  /* read_loadmap */
   NULL,  /* process_qsupported */
   NULL,  /* supports_tracepoints */
   NULL,  /* read_pc */

gdbserver/nto-low.cc

@@ -947,7 +947,6 @@ nto_sw_breakpoint_from_kind (int kind, int *size)
 static nto_process_target the_nto_target;
 
 static process_stratum_target nto_target_ops = {
-  NULL, /* read_loadmap */
   NULL, /* process_qsupported */
   NULL, /* supports_tracepoints */
   NULL, /* read_pc */

gdbserver/server.cc

@@ -1792,13 +1792,13 @@ static int
 handle_qxfer_fdpic (const char *annex, gdb_byte *readbuf,
 		    const gdb_byte *writebuf, ULONGEST offset, LONGEST len)
 {
-  if (the_target->read_loadmap == NULL)
+  if (!the_target->pt->supports_read_loadmap ())
     return -2;
 
   if (current_thread == NULL)
     return -1;
 
-  return (*the_target->read_loadmap) (annex, offset, readbuf, len);
+  return the_target->pt->read_loadmap (annex, offset, readbuf, len);
 }
 
 /* Handle qXfer:btrace:read.  */
@@ -2380,7 +2380,7 @@ handle_query (char *own_buf, int packet_len, int *new_packet_len_p)
       if (the_target->pt->supports_qxfer_siginfo ())
 	strcat (own_buf, ";qXfer:siginfo:read+;qXfer:siginfo:write+");
 
-      if (the_target->read_loadmap != NULL)
+      if (the_target->pt->supports_read_loadmap ())
 	strcat (own_buf, ";qXfer:fdpic:read+");
 
       /* We always report qXfer:features:read, as targets may

gdbserver/target.cc

@@ -589,3 +589,16 @@ process_target::core_of_thread (ptid_t ptid)
 {
   return -1;
 }
+
+bool
+process_target::supports_read_loadmap ()
+{
+  return false;
+}
+
+int
+process_target::read_loadmap (const char *annex, CORE_ADDR offset,
+			      unsigned char *myaddr, unsigned int len)
+{
+  gdb_assert_not_reached ("target op read_loadmap not supported");
+}

gdbserver/target.h

@@ -70,10 +70,6 @@ class process_target;
    shared code.  */
 struct process_stratum_target
 {
-  /* Read loadmaps.  Read LEN bytes at OFFSET into a buffer at MYADDR.  */
-  int (*read_loadmap) (const char *annex, CORE_ADDR offset,
-		       unsigned char *myaddr, unsigned int len);
-
   /* Target specific qSupported support.  FEATURES is an array of
      features with COUNT elements.  */
   void (*process_qsupported) (char **features, int count);
@@ -486,6 +482,13 @@ public:
 
   /* Returns the core given a thread, or -1 if not known.  */
   virtual int core_of_thread (ptid_t ptid);
+
+  /* Returns true if the read_loadmap target op is supported.  */
+  virtual bool supports_read_loadmap ();
+
+  /* Read loadmaps.  Read LEN bytes at OFFSET into a buffer at MYADDR.  */
+  virtual int read_loadmap (const char *annex, CORE_ADDR offset,
+			    unsigned char *myaddr, unsigned int len);
 };
 
 extern process_stratum_target *the_target;

gdbserver/win32-low.cc

@@ -1852,7 +1852,6 @@ win32_sw_breakpoint_from_kind (int kind, int *size)
 static win32_process_target the_win32_target;
 
 static process_stratum_target win32_target_ops = {
-  NULL, /* read_loadmap */
   NULL, /* process_qsupported */
   NULL, /* supports_tracepoints */
   NULL, /* read_pc */